The deeply-staggered mobile deployment of military defense forces generally imposes high logistics requirements even if only the ammunition supply is considered. Advantageously high-rate firepower usually requires a correspondingly high rate of munitions supply as well as a sufficient and timely replenishment of the latter at the firing site.
With hand weapons there is a tendency to move to smaller caliber ammunition with a higher muzzle velocity and greater weapon-firing cadence to simplify the handling of the weapon and increase its fire power. Naturally, this can be accomplished only at the expense of a reduced firing range.
With small-caliber ammunition, especially so-called casingless munitions, at least a step forward is possible toward the goal of increasing the resupply volume. The logistical demands can thus be relieved, the storage and supply problems at the firing site alleviated and, in addition, the quantity of ammunition which must be carried by the individual soldier may then be reduced so as to be less burdensome.
However, with automatic cannons, logistic requirements relief is not possible to the same degree as it is with hand weapons. This is because, owing to the widely diverse field tasks and the different types of ammunition required (e.g. explosive, incendiary or armor-piercing), the caliber can be modified only to a limited extent. Here, practically the only positive effect on the logistical problems can be achieved through the use of projectiles of the casingless type.
Yet, single-barrel automatic weapons currently in use by the armed forces are generally poorly suited to the firing of unitary projectiles without casings. The reason for this is, on the one hand, the diversity of the mechanical stresses to which the various ammunition types are subjected and, on the other hand, the nature of the firing cycle and of the weapon components functionally participating in it.
With casingless munitions, no spent cartridges accumulate at the firing site. Thus, the quick-acting shell-extraction and ejection devices, which would be required in automatic weapons for removal of the fired-shell casings, are not needed. As a result, the structure of the weapon is simplified and its physical length can be significantly decreased.
It should be noted, moreover, that the aforementioned casing-removal devices also serve for the removal of duds or misfires to eliminate the risk of untimely detonation of the propellant charge by the thermal action of the heated weapon. The need for opening the breech of the weapon to remove such a dud or misfire is thus a drawback since it endangers the personnel.
However, with the use of casingless munitions rounds, it is also important to recognize that their transport from the usual magazine and their feeding to the weapon must be carried out with a lesser stress factor imparted to these rounds than is the case with cartridge-type or casing munitions.
Efforts have been made to improve upon weapons systems in a general way to reduce their construction and operating costs, to standardize them, or make them more rationally fit into the logistics arrangements for military operations. In the case of mobile weapons, for example, the gun mount must be so constructed as to take into consideration not only the recoil components upon firing so that the reaction forces can be held as low as possible, but also must create the circumstances for lightweight construction to facilitate mobility of the weapon.
In the supply of munitions to such weapons, furthermore, it is necessary to consider not only the handling of the munitions, the rate of supply and their advance toward the weapon, but also the different charge types, munitions functions and like considerations in designing the gun mount.
Finally, it is important to create a weapons system which is as maintenance-free as possible so that restoration, repair and down time are held to a minimum while the operating times and the life of the system are lengthened as much as possible.
One-piece munitions without a charge-receiving casing are often called "cartridges". The type of one-piece munitions to which the present invention is directed, however, has a propellant charge which is not surrounded by a cartridge or casing and which has the projectile fitted to a shaped charge at the leading end thereof. For the sake of clarity, in this description, such unitary rounds will be referred to by the acronym PRUNIT formed from the words projectile and unit. A prunit is thus a single-piece type of munitions without a charge-receiving sleeve or casing in which the projectile proper is bonded to a cast or pressed body formed from the propulsion charge.
In the published German application (Offenlegungsschrift) DT-OS 2 102 310, there is described an automatic weapon which is constituted as a single-barrel automatic cannon using casingless munitions. In this instance, the propellant charge is in the form of a liquid or gaseous medium which must be supplied to the weapon in predetermined (metered) quantities. Published German application (Offenlegungsschrift) DT-OS 2 135 001 describes an automatic weapon for projectiles that are separate from the solid-charge body.
In both cases, there still remains the problem of supplying or otherwise coordinating the joint delivery of the projectile and the charge at high weapon-operating cadences and at the desired location. To this end, special devices and control means are required which complicate the weapon by comparison to weapons operating with prunit munition rounds.